As a fledgling commuter I have been carefully observing train sleepers, sleeper haters and the insides of my eyelids. To help other AM train newbies, here's a simple guide to making it to London alive and dribble free.
1. Before attempting the morning sleep complete the following steps.
a. Analyse your past sleep behaviour. Are you a walker or a talker? Call your ex and ask them if you snore. Have a snooze on the sofa and establish whether or not you are likely to sprawl. Check your pillow for drool. Categorize the above behaviours from 1-5 where 1 is never and 5 is always/severe. If you score more than 8 points you should never attempt to sleep on the train as you are likely to be clubbed to death with a briefcase by that banker you snuggled, dribbled on and called mummy. At the very lest you'll end up dribbly and ashamed at Charing Cross as death-stares follow you all the way to the Bakerloo.
b. Work out when you need to wake up for your stop. Set an alarm. Without this there will come a day where dreams of showjumping bunnies will carry you all the way to the end of the line, avoid at all costs.
c. Drink water, not juice. Juice will make you dribble, dribble will make you ashamed. You'll also feel about 8 times perkier when you wake up again. Needless to say espresso is also not your sleep buddy.
d. Make up a good sleep excuse. If you are a hugger and end up overly intimate with a fellow assenger, a heartfelt story of a night in emergency vetinary surgery, or a child with croup (that still happens right?) is much better than trying to explain that you just couldn't not watch the latest series of Toddlers and Tiaras.
2. While step one relates to humiliation avoidance. Step 2 is all about practicality. Which side is the sun? Avoid it. Sit by the window as occasional head bumps are much less embarrassing than toppling in to the aisle (field test #15 21/08/12). Dress appropriately, sleeping you is much less concerned about keeping her knees together and shirt pulled up, and no-one really wants to see that. Also, train air-con is cold, so don't get all trigger happy with the British summer and wear a chiffon shirt in September.
With all the above in place you may now enjoy a stress free, mildly refreshing and only occasionally bumpy train-sleeping career.